Lithium ion battery and its positive material

Abstract

The invention discloses a lithium ion battery and a positive material, the positive material possesses a core-shell structure, the material of a core layer is at least one of lithium cobaltate, a ternary material and a lithium manganese material, the material of a shell layer is lithium nickel manganese spinel. The preparation method comprises the following steps: preparing the sol shell layer material, then adding the core layer material in the sol, stirring, drying and calcining to prepare the lithium ion battery positive material with the core-shell structure. In addition, the invention also discloses the lithium ion battery prepared by the positive material with the core-shell structure, the end of charge voltage is 4.3-4.7V(vs. Li), the lithium ion battery has excellent charge and discharge cycling performance and high temperature storage performance under high voltage.

Description

technical field

[0001] The invention relates to the field of lithium ion batteries, in particular to a lithium ion battery and its positive electrode material. Background technique

[0002] With the miniaturization and thinning of portable electronic devices such as mobile phones, digital cameras, and notebook computers, the market's requirements for the energy density, cycle life, and safety performance of lithium-ion batteries continue to increase.

[0003] Lithium-ion batteries generally include: a positive electrode sheet, a negative electrode sheet, a separator spaced between the positive and negative electrode sheets, and an electrolyte, wherein the positive electrode sheet includes a positive electrode collector and a positive electrode material distributed on the positive electrode collector, and the negative electrode sheet includes The negative electrode collector and the negative electrode material distributed on the negative electrode collector. At present, the ...

Examples

Embodiment 1

[0034] At 25°C, weigh 2.93g of lithium acetate, 10.19g of manganese acetate, 3.40g of nickel acetate, and 0.22g of chromium nitrate into 400ml of water, and stir to dissolve them to form a lithium-nickel-manganese-chromium mixed solution; weigh 17.98g of lemon Add the acid to 400mL of water, stir to dissolve it; add the mixed solution of lithium nickel manganese chromium to the citric acid solution, adjust the pH of the solution to 6; stir at 60°C to form a sol; add 250g Li 1.02 co 0.988 Mg 0.01 Ti 0.002 o 2 powder, stirred evenly, and reacted at 60°C to obtain a deposit; after drying the obtained deposit at 100°C, it was first calcined at 950°C in an air atmosphere for 8 hours, and then at 650°C in an air atmosphere for 4 hours to obtain a coated 2wt% Li 1.02 co 0.988 Mg 0.01 Ti 0.002 o 2 / Li 1.03 Ni 0.49 mn 1.49 Cr 0.02 o 4 Cathode material with core-shell structure.

[0035] The lithium ion battery positive electrode material Li with core-shell structure prepa...

Embodiment 2

[0037] At 25°C, weigh 0.96g of lithium nitrate, 5.00g of manganese nitrate, 1.81g of nickel nitrate, and 0.35g of magnesium nitrate, add them to 200ml of ethanol, stir to dissolve them, and form a mixed solution of lithium, nickel, manganese and magnesium; weigh 1.86g of lemon Add the acid to 200mL ethanol, stir to dissolve it; add the mixed solution of lithium, nickel, manganese and magnesium to the citric acid solution, and adjust the pH of the solution to 5; stir at 45°C to form a sol; add 250g Li 1.08 CoO 2 Powder, stirred evenly, reacted at 50°C to obtain a deposit; after drying the obtained deposit at 100°C, first roasted at 800°C under an oxygen atmosphere for 6 hours, and then at 600°C for 4 hours under an oxygen atmosphere to obtain a coated 1wt% Li 1.08 CoO 2 / LiNi 0.45 mn 1.45 Mg 0.1 o 4 Cathode material with core-shell structure.

[0038] The lithium ion battery positive electrode material Li with core-shell structure prepared according to the above method ...

Embodiment 3

[0040] At 25°C, weigh 0.821g of lithium nitrate, 4.107g of manganese nitrate, 1.571g of nickel nitrate, 0.088g of chromium nitrate, and 0.006g of lithium fluoride into 200ml of ethanol, stir to dissolve them, and form a lithium-nickel-manganese-chromium mixed solution; Weigh 1.75g ​​of citric acid and add it to 200mL ethanol, stir to dissolve it; add lithium nickel manganese chromium mixed solution to the citric acid solution, adjust the pH of the solution to 6; stir at 45°C to form a sol; add 250g LiCo 0.91 Mg 0.9 o 2 powder, stirred evenly, and reacted at 50°C to obtain a deposit; after drying the obtained deposit at 100°C, it was first calcined at 800°C for 6 hours in an oxygen atmosphere, and then at 600°C for 6 hours in an oxygen atmosphere to obtain a clad 0.8wt% LiCo 0.91 Mg 0.9 o 2 / Li 1.08 Ni 0.49 mn 1.49 Cr 0.02 o 3.9 f 0.1 Cathode material with core-shell structure.

[0041] The lithium-ion battery cathode material LiCo with core-shell structure prepared ...

technical field

[0001] The invention relates to the field of lithium ion batteries, in particular to a lithium ion battery and its positive electrode material. Background technique

[0002] With the miniaturization and thinning of portable electronic devices such as mobile phones, digital cameras, and notebook computers, the market's requirements for the energy density, cycle life, and safety performance of lithium-ion batteries continue to increase.

[0003] Lithium-ion batteries generally include: a positive electrode sheet, a negative electrode sheet, a separator spaced between the positive and negative electrode sheets, and an electrolyte, wherein the positive electrode sheet includes a positive electrode collector and a positive electrode material distributed on the positive electrode collector, and the negative electrode sheet includes The negative electrode collector and the negative electrode material distributed on the negative electrode collector. At present, the ...

Examples

Embodiment 1

[0034] At 25°C, weigh 2.93g of lithium acetate, 10.19g of manganese acetate, 3.40g of nickel acetate, and 0.22g of chromium nitrate into 400ml of water, and stir to dissolve them to form a lithium-nickel-manganese-chromium mixed solution; weigh 17.98g of lemon Add the acid to 400mL of water, stir to dissolve it; add the mixed solution of lithium nickel manganese chromium to the citric acid solution, adjust the pH of the solution to 6; stir at 60°C to form a sol; add 250g Li 1.02 co 0.988 Mg 0.01 Ti 0.002 o 2 powder, stirred evenly, and reacted at 60°C to obtain a deposit; after drying the obtained deposit at 100°C, it was first calcined at 950°C in an air atmosphere for 8 hours, and then at 650°C in an air atmosphere for 4 hours to obtain a coated 2wt% Li 1.02 co 0.988 Mg 0.01 Ti 0.002 o 2 / Li 1.03 Ni 0.49 mn 1.49 Cr 0.02 o 4 Cathode material with core-shell structure.

[0035] The lithium ion battery positive electrode material Li with core-shell structure prepa...

Embodiment 2

[0037] At 25°C, weigh 0.96g of lithium nitrate, 5.00g of manganese nitrate, 1.81g of nickel nitrate, and 0.35g of magnesium nitrate, add them to 200ml of ethanol, stir to dissolve them, and form a mixed solution of lithium, nickel, manganese and magnesium; weigh 1.86g of lemon Add the acid to 200mL ethanol, stir to dissolve it; add the mixed solution of lithium, nickel, manganese and magnesium to the citric acid solution, and adjust the pH of the solution to 5; stir at 45°C to form a sol; add 250g Li 1.08 CoO 2 Powder, stirred evenly, reacted at 50°C to obtain a deposit; after drying the obtained deposit at 100°C, first roasted at 800°C under an oxygen atmosphere for 6 hours, and then at 600°C for 4 hours under an oxygen atmosphere to obtain a coated 1wt% Li 1.08 CoO 2 / LiNi 0.45 mn 1.45 Mg 0.1 o 4 Cathode material with core-shell structure.

[0038] The lithium ion battery positive electrode material Li with core-shell structure prepared according to the above method ...

Embodiment 3

[0040] At 25°C, weigh 0.821g of lithium nitrate, 4.107g of manganese nitrate, 1.571g of nickel nitrate, 0.088g of chromium nitrate, and 0.006g of lithium fluoride into 200ml of ethanol, stir to dissolve them, and form a lithium-nickel-manganese-chromium mixed solution; Weigh 1.75g ​​of citric acid and add it to 200mL ethanol, stir to dissolve it; add lithium nickel manganese chromium mixed solution to the citric acid solution, adjust the pH of the solution to 6; stir at 45°C to form a sol; add 250g LiCo 0.91 Mg 0.9 o 2 powder, stirred evenly, and reacted at 50°C to obtain a deposit; after drying the obtained deposit at 100°C, it was first calcined at 800°C for 6 hours in an oxygen atmosphere, and then at 600°C for 6 hours in an oxygen atmosphere to obtain a clad 0.8wt% LiCo 0.91 Mg 0.9 o 2 / Li 1.08 Ni 0.49 mn 1.49 Cr 0.02 o 3.9 f 0.1 Cathode material with core-shell structure.

[0041] The lithium-ion battery cathode material LiCo with core-shell structure prepared ...

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